Pohang University of Science and Technology POSTECH researchers said on the 11th that they had successively developed a metalens technology that produces sharp full-color images with a single thin lens and a manufacturing process that can mass-produce it. The research results were published in the international journal Nature Communications.
A metalens is an ultrathin lens that controls the direction of light by arranging structures the size of nm (nanometers, one-billionth of a meter). Because it can reduce conventional optical systems that use multiple glass lenses, it is being studied as a technology for Augmented Reality (AR) and Virtual Reality (VR) devices and next-generation displays.
However, for commercialization, "achromatic aberration" performance that brings red, green, and blue (RGB) light to the same point to reduce color fringing and mass-production technology are needed. In particular, it was not easy to achieve this with low-refractive-index materials, which have lower expense.
The researchers solved the problem by adjusting not only the width but also the height of the "meta-atoms," the nano pillars that make up the metalens. Each meta-atom was given a different height to more precisely control light at each wavelength.
In the first study, they fabricated nano structures of different heights using "two-photon lithography," a three-dimensional (3D) nano process. After building design data for various structures, they used artificial intelligence (AI) to place suitable structures at each lens position. Through this, they implemented a full-color metalens with a low-refractive-index material, and in experiments combined with an organic light-emitting diode (OLED) display, they also confirmed color images.
The second study focused on increasing the feasibility of mass production. They fabricated a mold engraved with nano structures of different heights using "grayscale electron-beam lithography," then applied it to a nanoimprint process that repeatedly transfers the pattern. A key feature is the ability to implement structures with a variety of heights at once compared with conventional methods.
The researchers explained that these two studies are meaningful in that they improved the optical performance of metalenses using low-refractive-index materials while presenting a manufacturing method that enables repeated production.
Professor Noh Joon-seok said, "By using high-dimensional nano processing, we presented the manufacturability of full-color achromatic metalenses for AR and VR," and "we expect they can be applied in a variety of fields such as displays, imaging, and optical sensors."
References
Nature Communications (2026), DOI: https://doi.org/10.1038/s41467-026-73103-2
Nature Communications (2026), DOI: https://doi.org/10.1038/s41467-026-73940-1